(1) Field of the Invention
The present invention relates to a method and a system for searching and collecting data from information providing servers, that is, World Wide Web (WWW) servers through the Internet. More particularly, the present invention is related to a method and a system for searching data requested from a plurality of client terminals collectively at fixed intervals of time (at fixed times) according to the reserved search requests from those client terminals and distributing searched data to each of those client terminals.
(2) Description of Related Art
Now that the use of the Internet has come into an explosive increase, it is possible to access World Wide Web (WWW) servers, which are information providing servers connected to the Internet, from any place in the world. The Internet and the WWW are described in detail in the following publications.
(1) Internet User""s Guide; written by Ed Krol, translated by Jun Murai, and published by Tomson Publishing Japan.
(2) The Whole Internet; written by Ed Krol and published by Oreilly Associates, Inc. which is an original of the publication (1).
If an Internet user makes an attempt to obtain data from a WWW server, for example, using a client terminal, which is a personal computer (PC) or a work station (WS) so as to collect data distributed throughout the world, the user may have to wait for a long time until he/she obtains desired data after he/she issues a request depending on the operation hour and the object WWW server. This problem may also occur in the following cases; when the accessed Internet route is insufficient in capacity to cope with the access speed, when accesses to a specific WWW server are over-concentrated, and when the access is made via a specific relay point (generally, it is also referred to as a hub).
Now that the Internet allows data to be searched from WWW servers disposed distributively throughout the world, such the advantage of the Internet should be used more practically.
Using a communication satellite will be one of the effective methods for obtaining data from Internet WWW servers at high speeds. Such two-way communications, however, require an expensive transmitting facility. Practically, therefore, such a communication satellite is usually used only for receiving data from WWW servers.
On the other hand, the user may search and collect data regularly and search and collect non-emergency data from WWW servers connected to the Internet at fixed intervals of time. In such non-real time data searching, it would be convenient if it is possible that reserved search requests are registered beforehand so that WWW servers are accessed at fixed intervals of time, although such a function is not realized yet.
Under such the circumstances, it is an object of the present invention to provide a method and a system that can reserve a search item beforehand from a client terminal and distribute data searched from an object Internet WWW server according to the reserved search item to the client terminal collectively at fixed intervals of time when searched information is to be obtained from an information providing server connected to the Internet.
It is another object of the present invention to provide a method and a system that can receive searched data collectively from an object Internet WWW server at fixed intervals of time via a communication satellite and distribute received searched data to the request source client terminal.
In order to achieve the above mentioned objects, the reserved request type of information search and distribution system of the present invention is provided with a searching server and a satellite communication server so that the system can process reserved search requests from client terminals.
Receiving a reserved search request from a client terminal, the searching server searches specified data from each WWW server connected to the Internet and saves searched data in a cache file provided in the searching server. After this, the system transmits collected searched data to the client terminal sequentially.
According to the present invention, collected data is transmitted to the object client terminal, for example, at 12 a.m., at 8 a.m., at noon, at 5 p.m. every day, or when the client terminal is connected to the searching server.
Furthermore, the above mentioned searching server is provided with a function for communicating with a network access center of the Internet so that the server can issue reserved search requests from a plurality of client terminals collectively to the network access center, and the network access center operates to search and collect data from WWW servers connected to the Internet.
Such a network access center is convenient to search and collect data from object WWW servers instead of a searching server when those WWW servers exist in a specific relay point or in a specific relay area in a different country in which the searching server does not exist, for example, when the searching server exists in Japan and the object WWW servers and the network access center exist in the United States of America.
The data searched and collected by the network access center from WWW servers is transmitted to a satellite communication server via a communication satellite. The satellite communication server transfers the received data to the searching server sequentially. The searching server saves data received from the satellite communication server in a cache file sequentially. Then, in a fixed time, the searching server reads the data from the cache file and transmits it to the object client terminal.
According to the present invention, by using the satellite communication server as a communication unit for exclusively receiving the searched data from the communication satellite, the data searched from WWW servers existing in a specific relay area can be received collectively at a high speed so as to reduce the required searching and collecting time significantly.